Clutch control mechanism



E. R. PRICE ET AL.

CLUTCH CONTROL MEGHANISM March 28, 1939.

4 Sheets-Sheet 1 Filed sept. 2e, 1955 34 /m J6 V /Z4 BY "f7- I AT oRNEYMarch 28, 1939- EV R. PRICE ET AL 2,152,088

CLUTCH CONTROL MECHANI SM Filed sepi. 26, 1955 4 sheets-sheet 2A A TORNEY March 28, 1939. E, R, PR'ICE ET Al. 2,152,088

CLUTCH CONTROL MECHAN I SM Filed sept. 2e, 1935 4 sheets-sheet s Y "gg94 6" 6 INVENTog. v

' A TORNEY March 28, 1939*. E. R. PRICE r-:T A1.

CLUTCH CONTROL MECHANISM Filed Sept. 26, 1935 4 Sheets-Sheet 4 mummy- R.ni. www T M A. l .0 M

'Patented Mar. 2s, 1939 UNITED ,STATES CLUTCH CONTROL MECHANISM Earl R.Price and Harold W. Price, South Bend, Ind., assignors to BendixProducts Corporation, South Bend, Ind., a -corporation of IndianaApplication september 26,1935, seria1`No.42,zo1

l e claims. cl. 19e-.91)

This invention relates to automotive clutch control mechanism, and moreparticularly to an accelerator controlled power mechanism for operatingthe clutch in such fashion as to' closely 5 simulate a skillful manualoperation thereof.

Heretofore in the development of this art the mechanism was designed toautomatically disengage the clutch upon release of the accelerator andupon depression of the accelerator to initiate 0 a two-stage engagementofthe clutch the rate of clutch movement during the second stagedepending upon the position of the accelerator. However, such mechanism,in a measure, proves unsatisfactory, inasmuch as the engagement of theclutch is automatically completed with each and every throttle-openposition of the accelerator, no means being provided fora so-calledmaneuvering control of the clutch in coordination with the opening ofthe throttle. This latter operation of the throtne'and clutch is thatwhich is effected in a conventional operation of an automotive vehicle.The accelerator is alternately depressed and released by the right footof the driver as the clutch pedal is depressed and released by the leftfoot, the two being coordinated in such fashion as either to moveforward or to back up the vehicle in accordance with torquerequirements, that is, smoothly and with the least wear and tear on boththe engine and the clutch.

This invention is accordingly directed to a clutch operating powermechanism 'wherein the clutch engagement control, that is the control ofthe clutch plate loading pressures, is so correlated with the degree ofthrottle opening as to closely simulate a conventional manual operationof the throttle and clutch.' To this end there is provided a clutchoperating pressure differential operated motor, the control valvethereof being of 40 the pressure balanced follow-up type and operated bythe accelerator. For a given position of the accelerator there is 'thuseffected a corresponding position of the clutch to control both theengagement and the disengagement thereof.

A further object of the invention is to provide means for so controllingthe aforementioned power means, as to limit the clutch plate loadingpressure to a predetermined maximum, thus obviating any undesirablejerking of the vehicle.

A further object of the invention is to incorporate a check valve in theconnection between the source of power, preferably the intake manifold,and the differential pressure motor, thus providing an additional meansfor limiting the clutch -plate loading pressure' to a predeterminedmaximum.

AYet another object of the invention is to provide power means,controlled in part by the accelerator, operative to permit the clutch tomove 5 relatively rapidly, under the action of the clutch springs, up tothe cushioning point in the engagement of the clutch and to thereaftermove either continuously or intermittently, depending upon the mode ofoperation of the accelerator. l 10 Yet another object of the inventionis to provide power means, controlled by both th transmission and byeither a circuit breaker or by theA brake pedal, said power means beingoperative, when the transmission is in high gear, to cut out l5 theclutch operatingpower means, unless and until the brake is applied orthe engine speed drops to a predetermined minimum, whereupon the powermeans automatically again becomes operative to dsengage the clutch. Afurther object of the invention is to provide a valve mechanismoperative for accomplishing the desired results above referred to andwherein the mechanism is extremely simple in construction and economicalto manufacture in view of 25 the relatively few parts and fewadjustments of those parts.

' Other objects of the invention and desirable details of constructionand combinations of'parts will become apparent from a detaileddescription 3G of certain embodiments of the invention, described indetail in the following specification, taken in conjunction with theaccompanying drawings illustrating said embodiments, in which:

Figure lis a diagrammatic View of the pre 35 ferred form of clutchcontrol mechanism constituting our invention;

Figure 2 is a sectional view of the control valv mechanism of Figure l,the valve parts being shown in their clutchdisengaged position; 40

Figure 3 is a sectional view of the valve mechanism, the valve partsbeing in their lapped position to maintain the 'clutch at the so-calledcushion point;

Figure 4 is another sectional view of the valve 45 mechanism, the partsbeing in the so-called cracked position to initiate a further engagementof the clutch; l.

Figure 5 is a transverse sectional view of the valve mechanism, takeno'n the line 5 5 of 50 Figure 2; i

Figure 6 is a longitudinall sectional view of a modied form ofvalve'mechanism;

Figure '7 is a sectional view of the pressure differential operatedclutch motor; 55

Figure 8 is a diagrammatic view of a combined high gear lock-out andcircuit breaker cut-in hookup for the clutch control mechanism of Figure1; and

Figure 9 is a diagrammatic view of a hookup similar to that of Figure 8with the exception that a brake pedal operated clutch control cut-inswitch is substituted for the circuit breaker operated switch of Figure8.

Referring to the clutch mechanism of Figure l, a conventional clutch Iof the friction disc type is adapted to be operated either manually by aclutch pedal l2 and linkage lil or by power through the medium of apressure diierential motor IIS, Figure 7, comprising a cylinder i8 anddiaphragm 20, the latter being connected to the clutch by a link 22 andthe aforementioned linkage ld. The motor I6 is placed in fluidtransmitting connection with an intake manifold 28 by means of conduits26 and 28, the two being interconnected by a control valve unit 30. Anaccelerator 32 is operatively connected to a butterfly valve 3d of athrottle mechanism'by a link 3S, cross shaft 38, crank 4U and link ft2and to the valvular unit 3D by link 42, cranks 40 and alli, link 58,bell crank 52 and link 5l?.

Referring now to the valve unit 3B, the same comprises a casingincluding sections 56 and 58 xedly secured to the engine, preferablyadjacent the intake manifold and the clutch motor, as disclosed inFigure l. Sections 6 and 58 retain between them a flexible diaphragm 60fixedly secured at its center, by fastenings 62 and 68, to a sleevevalve member 8E provided with an annular series of ports 6,8 and asecond annular series of ports lll. The valve member 86 is urged to theleft by a spring 72. A valve plunger member "ill, slidably mountedwithin the sleeve valve 68, is urged into engagement with a valveoperating cam lever member 'i6 by a spring 18, saidlever member being/pivotally connected at one end to the accelerator operated link 54 andat its other end to a lever 80 pivoted intermediate its ends to abracket 82 secured-to the valve casing.

Describing now the operation of the aforementioned mechanism, uponrelease of the accelerator 32, an accelerator return spring 8e acts toforce the cam lever T6 against a stop 86 and then move both levers i6and 88 as a unit tol force the valve plunger 'itl to 'the positiondisclosed in Figure 2. In this position a recess 88, provided by virtueof a triangular-shaped bodyportion 9D vof the valve plunger 7d,registers with one of the ports l0 in the sleeve'valve '86 and therebyinterconnects a suction compartment 92 of the clutch motor l5 to themanifold via conduit 26, a duct 9.1i in the valve casing, port lll,recess 88, port 68, a compartment 96 the valve casing, a port 98, andconduit 28.

The engine, now idling by virtue of the closed throttle, induces avacuum in the intake manifold and the clutch m'otor compartment 92 isaccordingly partially evacuated to thereby energize the clutch motor anddisengage the clutch.

The transmission may now be operated to select the desired gear ratio,whereupon it is necessary to reengage the clutch. This is effected bydepressing the accelerator until the lost motion at a slot 588, Figurel, is taken up. The accelerator being in this position, the valve spring78, which is weaker `than the accelerator return spring 81S,

isoperative to move the plunger llland levers i8 and 8i! to the positiondisclosed in Figure 3. In this position an adjustable stop M2 secured tothe lever 8@ contacts the bracket 82. In this operation the plunger 'Iismoved relative to the sleeve valve 66 to iirst cut off thecommunication between the recess 88 and the slot '10,.Figure 2, andsubsequently move the plunger relative to the sleeve valve to therelative position of the valve parts disclosed in Figure 4. Air is thenadmitted to the chamber 92 of the'motor, as' part disclosed by thearrows in Figure 4, the'air. entering Via ports H04 inthe valve section`56, recess 88, ports 68, valve chamber 96, port 98, and conduit 28. Theplunger M being held in the aforementioned position, the sleeve valve 66then moves to the left, as the gaseous pressure in the chamber 98 isincreased. .This movement is terminated when the valve is said to belapped, which is the position of the valve parts disclosed in Figure 3,connection` between both the atmosphere and manifold to the clutch motorbeing cut off.

The vacuum Within the motor chamber 92 at this time is just sufficientto maintain the clutch plates in non-driving position. Thus with theaccelerator moved to the cushion point, that is with the stop l02abutting the bracket 82, the driving clutch plate is automatically movedjust to the aforementioned position and no further.

The stop m2 is adjusted from time to time for clutch plate wear.

Further opening movement of the accelerator is met by the resistance ofabutterfly valve` return spring H16, thus apprisingl the driver that thethrottle is about to be opened and the clutch engaged. Such movementmerely repeats the above described cycle of valve operations, that is arecracking of the valve to admit additional atmosphere to the chambers96 and 92 and a subsequent follow-up action of the sleeve valve 6 6l tolap the valve and hold the clutch engaged at a given loading.

Thus the degree of clutch plate loading is determined by thedegree ofdepression oi' the accelerator, the throttle at the same time beingopened to a greater degree to increase the engine torque. The face ofthe cam of lever i6 may be contoured to eect any desired relativethrottle opening and clutch engagement.

Should the driver wish to slightly release the clutch, as might bedesired in maneuvering the vehicle into a parked position, he has merelyto slightly release the accelerator, whereupon the Should a greaterdegree of throttle opening Y be desired for a given clutch plateloading, such may be accomplished by more or less quickly depressing theaccelerator, whereupon the throttle is opened to increase the R. P. M.of the engine prior to eiecting the clutch plate loading for the givenposition of the throttle. Such an action results in part by virtue ofthe time lag in the operation of the power mechanism.

It is desirable to limit thel degree of clutch plate loading in order toobviate a grabbing clutch, and to this end there is provided a stopmechanism comprising a nut mounted on the end of the valve plunger 7f3and contactible with the end wall of the valve casing at H8. Thus byadjusting the position of the nut 88 the driver may predetermine thelimiting position of the valveplunger M and thus 08 adjustably -dottedline position disclosed in bers and the manifold. This action-may occurshould the driver suddenly tramp upon the accelerator to open thethrottle wide and reduce the pressure of the manifold to that of theatmospliere, or substantially so.

AThere is disclosed in Figure 6 amodified form of valve mechanismwherein a casing, comprising parts ||4 and ||6, houses telescopingsleeve valve takenup, all aspreviously described.

' sults.

members ||8 and |20, the substantially elliptically shaped parts IIB'and |20' of which are so arranged and proportioned as to provide afollow-up valve mechanism of the type previouslydescribed. Valve springs|22 and |24 serveto actuate the valve members, and a stop member |26functions to limit the clutch engaging operation of the valve aspreviously described. The valve casing is ported at |28 and |30 toprovide connections' with the clutch motor. and intake manifoldrespectively. The valve operating mechanism of Figure 6 comprisespivotally connected levers |32 and |34, the latter being U- shaped andtheformer having a cam portion |36 contoured to effect the desiredrelative throttle opening and clutch plate loading. In the clutchengagingmovement of the levers, the two move as a unit by virtue of theaction of the accelerator return spring and the-valve spring |24, a stop|30 on the lever ,|32 abutting the bottomof the U-shaped lever |34. Thelatter contacts an adjustable stop |40 when the lost` motion in thethrottle operating link has been In all other respects the valvemechanism of Figure/ 6 functions in a manner similar to the mechanism ofFigures 2, 3 and 4.

It is desirable to cut out the power operation of the clutch when thetransmission is in high gear, thus eliminating the evils offree-wheeling and also obviating unnecessary wear of the 'clutchmechanism including the throw-out bearing thereof. It is, however,desirable to automatically again cut in the operation of the power meansand thus.' automatically disengage the clutch in the event that thewheel brakes are applied, or the speed of the vehicle or engine issubstantially reduced; otherwise, the engine would be stalled as the caris brought to a stop.

In Figures 8 and 9 there are disclosed mechanisms for accomplishing theabove described re- Referrirg to Figure 8, the high'and second gearshift rail |42 of a standard three-speeds forward and reverseVtransmission |44y is at all times in sliding contact with a pin |46 ofa switch mechanism |40. The switch |48 serves to either make or break acircuit from a battery |50 to a solenoid |52, the latter functioning to,operatea cut-out valve |54,l Figure 5. When a position, the rail |42-ismoved to seat the pin |46 j tomotive vehicle provided with a clutch, athrottle within a notch |58 in the'rail', 'thus automatically breakingthe switch |48 to` deenergize the solenoid |52A and permit a. spring|60r Figure 5,

to seat the valve; ,The clutch moton is thus rendisengage the. clutch,thus obviating a free-wheeling effect and utilizing the engine as abrake when traveling in high gear. However, should the transmission beleft in high gear and the engine speed dropped sufllciently to operateva conventional generator cut-out |62, a switch |64 is then closed, theswitch |48 being shunted, the

solenoid |52 again energized and the valve |54 to thus openthe valve |54and render the clutch operating power means operative.

The mechanism of Figure 9 functions similarly to that of Figure 8, abrake-pedal operated switch being substituted for the generator cutoutmechanism of Figure 8. In this embodiment of the invention, with thetransmission in high gear, the high and second gear shift rail |66 ismoved to register an insulated section |68 with switch contacts |10 and|12, thus breaking' the circuit between a battery |14 and a cut-outvalve operating solenoid |16. However, upon depressing a brake pedal|10, al switch is closed to shunt the aforementioned contacts and againenergize the solenoid |16 to open the cut-out valve. 'I'hus thetransmission may be left im,

high gear and theV clutch is automatically disengaged in bringing thevehicle to a stop.

Although this invention has been described in .connection with certainspeciiic embodiments,

the principles involved are susceptible of numerous other applicationsthat will readily occur to persons skilled in the art. The invention is,therefore, to be limited only as indicated by the scope of the appendedclaims.

We claim:

1. In a, clutch operatingvmechanism for an automotive vehicle providedwith aJ clutch, a throttle valve and an accelerator, a pressuredifferential operated .power device connected with the clutch, pressuresensitive valvular means for valve operation further effecting anarresting of the movement of the clutch elements at a point prior tooperative engagement, and then further releasing the clutch elementsvfor movement into operative engagement.

. 2. In a clutch operating mechanism for an auvalve and an accelerator,a pressure differential operated power device connected with the clutch,valvular means for controlling the. operation of said power device,linkage having a lost motion connection therein interconnecting saidthrottle valve and valvular means, said linkage further includingleverage-changing means; said valvular means including a plurality oftelescoping members operative upon movement of the accelerator to idlingposition for rendering the power device operative to disengage theclutch and operative upon movement of the accelerator toward openposition for successively releasing the clutch elements for movementtoward operative engagement, said valve operation further effecting anarresting movement of the clutch elements at a point prior to operativeengagement, and then furtherreleasing the clutch elements for movementinto operative engagement, said valvular means further including a stopmember to limit the clutch engaging operation thereof.

3. In a clutch operating mechanism for an automotive'vehicle providedwith a clutch, a throttle valve and an accelerator, a pressuredifferential operated power device connected with the clutch, valvularmeans for controlling the operation of said power device, linkagehaving' a lost motion connection therein interconnecting said throttlevalve and valvular means, said linkage further including aleverage-changing means, said valvular means including a plurality oftelescoping members operative upon movement of the accelerator to idlingposition for rendering the power device operative to disengage theclutch and operative upon movement o`f the accelerator toward openposition for successively releasing the Jclutch elements for movementtoward operative engagement, said valve operation further effecting anarresting movement of the .clutch elements at a point prior to operativeengagement, and then further releasing the clutch elements for movementinto operative engagement, said valvular means further including a stopmember to limit the clutch engaging operation thereof, and a check valvemechanism also operative to limit the clutch engaging operation ofthevalve mechanism.

4.- In a clutch operating mechanism for an automotive vehicle providedwith achange-speed transmission, on engine, a clutch, a throttle valveand an accelerator, a pressure diierential operated power deviceconnected with the clutch, pressure sensitive valvular means forcontrolling the operation of said power, device, linkage having a lostmotion connection therein interconnecting said throttle valve andvalvular means, said linkage further including a leverage-changingmeans,'said valvular means including a plurality of telescoping membersoperative upon movement of the accelerator to idling position to renderthe power device operative to disengage the clutch and operative uponmovement of the accelerator toward open position for successivelyreleasing the clutch elements for movement toward operative engagement,said valve operation eecting an arresting of the movement of the clutchelements at a point prior to operative engagement, and then furtherreleasing the clutch elements for movement into operative enaisaoeegagement, together with power operated means operative to cut the powerdevice out of operation, when and if the change-speed transmission ofthe vehicle is in high gear and the speed of the engine exceeds apredetermined factor.

- 5. In a clutch operating mechanism for an automotive vehicle providedwith ai change-speed transmission, an engine, a wheel brake, a clutch, athrottle valve and an accelerator, a. pressure differential operatedpowerdevice connected with the clutch, pressure'sensitive valvular meansfor controlling the operation. of said power device, linkage having alost motion connection therein interconnecting said throttle'valve,accelerator and valvular means, said linkage further including aleverage-changing means, said valvular Ameans including a plurality oftelescoping members operative upon movement of the accelerator to idlingposition to render the power device 0perative to disengage the clutchand operative upon movement of the accelerator toward open position forsuccessively releasingthe clutch elements for movement toward operativeengagement, said valve operation eiecting an arresting of the movementof the clutch elements at a point prior to operative engagement, andthen further releasing the clutch elements for movement into operativeengagement, together with power operated means operative to cut thepower device out of operation, when and if the change-speed transmissionof the vehicle is in high gear and the wheel brake is released.

6. The combination with a clutch, a throttle and an accelerator of amotor vehicle, of a pressure differential operated motor operablyconnected with the clutch, valve means including relatively movabletelescoping valve members for controlling the operation of said -motor,valve and throttle operating means .interconnecting said accelerator,throttle and valve means including a lost motion connection, and furtherincluding leverage-changing means and a stop, said valve being operativeupon vmovement of the accelerator to idling position vfor rendering themotor operative to disengage the clutch and operative upon movement ofthe accelerator toward open position for intermittently releasing theclutch elements for movement toward operative engagement, saidintermittent movement of the valve including, by virtue of theaforementioned stop and leverage-changing means, an arresting vof themovement of the clutch elements at a point prior to operativeengagement, and then lfurther releasing the clutch elements for movementinto operative engagement by successive l stages. l

HAROLD W. PRICE. EARL R. PRICE.

A CERTIFICATE OF CORRECTION. Patent-No. 2,152,088. A v March28, 1939. AEARL R. PRICE, ET AL. n It is hereby certified that error' appears inthe ,printed specifieation ofthe above numbered patent requiringcorrection as follows: Page 5, first column, line l5, for theWord-"parts" read ports; page h, first column, .line )40, claim LL, for"on" before "engine" read an;` and that the said Letters Patent shouldberead with this correction therein that the same may conform to therecord of the case in the Patent Office.

signe@ and sealed this 15th day of February, A. D. 19m.

Henry Van Arsdale, (Seal) Acting Commissioner of' Patents.

